Type printing telegraph and like apparatus



July 9, 1940. A. E. THOMPSON r AL 2,207,235

TYPE PRINTING TELEGRAPH AND LIKE APPARATUS Filed Sept. 4; 1957 2 Sheets-Sheet l I y 9, 1940- I A. E. THOMPSON El AL 2,207,235

TYPE PRINTING TELEGRAPH AND LIKE APPARATUS Filed Sefit. 4, 1937 2 Sheets-Sheet 2 llVVl-WTORS Patented July 9, 1940 v UNITED STAT-Es- TYPE PRINTING TELEGRAPH AND LIKE APPARATUS Alfred Edward" Thompson and'Reginald Dennis Salmon, Croydon, England, assignors to Creed andCompany Limited, Croydon, England Application September 4, 1937, SerialNo. 162,438 I In Great Britain November 27, 1936 2 Claims. (01.17849),

This invention relates to translating mechatwo positions by the link 9 driven from an ec nisms of the aggregate motion type for printing telegraph and like apparatus.

In such translating mechanisms backlash in the various sections of the mechanism may render the position of the final member indeterminate, and it has already been proposed to use a correcting device acting on the final member to ensure correct positioning thereof.

The possible error due to'backlash in the positions of members of the aggregate motion system other than the final one is less and the limits within which these other members must be positioned are wider than for the final member. For example, in an aggregate motion translating device for translating signals according to the five unit code into the positions of a typewheel, the final member has 32 possible positions and must be brought to the correct position within limits less than ,4 of a revolution. If the aggregate motion system used be that described in copending application No. 113,756 there are five planet wheels and five outer sunwheels to be moved thereby. The final sunwheel has 32 positions, but the next outer sunwheel has only 16 possible positions and only needs to be brought to the correct position within limits that are something less than of one revolution. I

If therefore a correcting device is caused to act upon the fourth outer sunwheel so as to brin it into the correct position the amount of error remaining in the position of the final member will be that due to backlash in the fifth section only and the permissible amount of backlash in this final section may be greater than would be permissible had the fourth section not been corrected.

According to this invention we provide two correcting devices acting upon two different portions of an aggregate motion system, the arrangement being such that the correcting device acting upon the member other than the final member operates before the correcting device cooperating with the final member.

The nature of the invention will be better understood from the following description taken in conjunction with the accompanying drawings in which Figs. 1 and 2 taken together and placed side by side with Fig. l to the left show one embodiment of the invention. The aggregate motion system comprises five similar sections of the kind described in copending application No. 113.-

756 the fifth section being shown in more detail than the others.

The planet wheel ll! swinging on the arm H is moved into one or other of the centric pin in driving disc 4 which is adapted to be driven by the ratchet wheel 6 and pawl 8 into one or other of two positions 180 apart, determined by the operation of the detents 2. The outer sunwheel of the final section is carried on a frame, shown diagrammatically at l3, which also carries the gear l4 driving the gear l5 mounted upon the spline shaft l6 upon which slides the gear 3| which drives the gear 32. The 10 gear 32 drives the typewheel 31 from the universal joint 33. The outer sunwheel in the fourth section of the aggregate motion system carries a corrector wheel l8 with which the roller 19 an the corrector lever 20 is adapted to cooperate.

The typewheel spindle 34 carries a corrector wheel 35 with which co-operates the corrector tooth 38. The typewheel spindle 34 is journalled at its upper end in a rocking frame 36 that is connected by a link 4| to lever 30. This lever is mounted upon a spline shaft 28 adapted to be rotated when required by the lever 23 which latter is moved by the link 24 from the printing lever 26. The lever 26 is arranged to be operated as the aggregate gear system comes 25 to rest, by a cam (not shown). The lever 23 also controls through the link 21 a lever 29 carry- 1 ing a pin 22. This pin 22 controls through the medium of spring 45 the movements of the corrector lever 20.

In the operation of the machine the detent levers 2 are selectively and simultaneously operated to allow the discs 4 to move into their. correct relative positions thereby rotating the several planet wheels corresponding to planet wheel in. The spline shaft l6, and thereby the typewheel 3! are thus positioned. When the typewheel comes to rest the printing lever 26 rotates in a clockwise direction so as to rotate the lever 29 also in a clockwise directiomthereby permitting the corrector lever 20 to fall upon the corrector wheel l8 on the fourth outer sunwheel. The action of the roller I 9 as it falls into the corrector tooth is such as to bring the fourth outer sunwheel to its correct position, thereby eliminating the effect of any backlash in any one of the first four sections of the aggregate motion system. The rotation of the lever 215 also acts to rotate the spline shaft 28 and thereby rotate lever 30 and the frame 36, thus causing 5 the typewheel toswing forward against the paper platen 42. Immediately before the typewheel strikes the paper platen, and just after the corrector roller l9 has corrected the outer sunwheel l8 the corrector wheel 35- is brought into cooperation with the corrector tooth 38 to correct the position of the typewheel. The corrector tooth 38 is mounted upon a member 48 that is held against a fixed stop 39 by means of a spring 44. Thus after the corrector 38 has engaged the corrector wheel 33 it can yield slightly, thereby permitting the typewheel to impact against the paper.

What is claimed is:

1. Translating mechanism of the aggregate motion type for printing telegraph apparatus comprising a plurality of serially connected members forming an aggegate motion system, separate correcting devices for acting upon the final member of said aggregate motion system and upon an intermediate member respectively, means for bringing the latter of said correcting devices into operation immediately before the operation of the former, said former correctin device comprising a type wheel, a correction wheel attached to said type wheel, a corrector tooth, means for initiating a printing movement, means for bringng said corrector wheel into cooperation with said corrector tooth in response to said printing movement and means for yieldably supporting said corrector tube to permit completion of the printing operation.

2. Translating mechanism of the aggregate motion type for printing telegraph apparatus comprising a plurality of serially connected members forming an aggregate motion system, separate correcting devices for acting upon the final member of said aggregate motion system and upon an intermediate member respectively, means for bringing the latter of said correcting devices into operation immediately before the operation of the former, a printing lever, and means responsive to operation of said printing lever for actuating said correcting devices.

ALFRED EDWARD THOMPSON. REGINALD DENNIS SALMON. 

